1. Field of the Invention
The invention generally relates to an optoelectronic device and an optical module, and more particularly, to a projection device and a lens module.
2. Description of Related Art
The projection device is a display device for producing a large-size screen frame. The imaging principle of the projection device is to convert an illumination beam produced by a light source into an image beam through a light valve, followed by projecting the image beam through a lens onto a screen or a wall surface to form images. Along with the progress of the projection technology and the decrease in manufacturing cost, the application of the projection device has been gradually expanded to the domestic use from the commercial use.
In general, the projection device includes a projection lens module, and the projection lens module includes a lens barrel and at least one lens disposed in the lens barrel. In the prior art, the lens is fixed at the lens barrel mostly by using a pressured ring, glue or a wire spring. However, these ways of fixing the lens have shortages of high manufacturing cost, poor assembling accuracy or low reliability, so that some projection lens modules fix the lens by a riveting process. Nevertheless, many projection lens modules have implementation limit on the above-mentioned riveting process due to the original design.
Taiwan Patent No. 582561 discloses a method of fixing the lens. Herein, a riveting knife is used to form folded pieces at the lens barrel in a destructive way. However, the proposed scheme still fails to reduce the traditional shortage of high manufacturing cost, poor assembling accuracy or low reliability.